How to get a fast time/high speed: Once you enter a race hit and try to get the rev in the green area. When the green light turns on hit upwards to change in to 1st gear, and when its in the green again hit upwards again to change to 2nd. Continue up through the gears and hopefully you will get a good result. That's how you do it in theory but its different from car to car how its done for the fastest time.
Another important thing if you are having trouble with the drag races is make sure you go just as the light turns green. Don't wait for it to turn green, get the light rhythm in your head and shift up just as it turn green. You can get around 0.2 seconds that way.

The best car to use is by far the Nissan Skyline GT-R (R32) Speedhunters in both drag and standing mile, once you tried them all you will know why.

1. If you are considering boosting Ready to Rock head over to the boosting thread and sign up.2. Complete 4 events in both Drag and Standing Mile, but remember to use a new car for each event to save some time for Speedhunter3. Win the Drag championship for Grim Reaper4. Win the Standing Mile championship for Monster Dog5. Finish of Speedhunter6. Get 250 Club and 8 Second Club if you don't have them already.

8 Second Club Ran a Quarter Mile in less than 9 seconds

Ready to Rock Won an Online event in a Speedhunters Edition Car

This trophy can be quite tricky because you need to find someone else with the Speedhunters DLC. If you create a lobby with the Speedhunters DLC enabled you might be lucky to get someone in it, but its quite rare.
Another option is of course to boost it. This can be done in any game mode and even in a private match, just make sure you enable the Speedhunters DLC and pick a car from the DLC.

Grim Reaper Beat Chris Rado and won the 1320 Outlaws Championship

To unlock the drag championship event you need to get 4 podium finishes. Chris Rado set times just above 9 seconds so take the Nissan Skyline GT-R (R32) Speedhunters or a similar car that does below 9 seconds, and you will win this championship without breaking a sweat.

Monster Dog Beat Koz and won the Standing Mile World Championship

To unlock the standing mile championship event you need to get 4 podium finishes.
Koz does around 220 mph (355 km/h) so again use the Nissan Skyline GT-R (R32) Speedhunters and beat the championship easily.

Speedhunter Complete a Career event in each of the Speedhunters Edition Cars

Once you won the 2 cars from Koz and Chris Rado you can complete this trophy. Simply use all 14 cars in any drag or standing mile event, but you can save some time if you use different cars in all the events leading up to the championships.